Ball joints having wear indicators are well known. By way of example, U.S. Pat. No. 3,813,178 discloses a ball joint having a wear indicator. The ball joint of U.S. Pat. No. 3,813,178 includes a ball supported for movement in a socket. The ball is located between a load carrying bearing ring and a wear take-up bearing ring. The ball slides against the surfaces of the bearing rings when it moves in the socket. The wear take-up bearing ring is spring biased to move toward the load carrying bearing ring to take-up wear between the ball and the bearing rings. When the wear take-up bearing ring moves, a protrusion on the wear take-up bearing ring moves into the socket so that the amount of wear is indicated by the amount that the protrusion moves into the socket.